Abstract: A quantum interference device includes a superconducting loop interrupted by a normal conductor segment, and an interferometer connected to the normal conductor segment, wherein the superconducting loop includes a plurality of turns. The turns can be a plurality of adjacent lobes. A coil can be located within a lobe of the superconducting loop. Optionally, a bridge layer (e.g., of gold) is formed above the substrate to make an electrical contact between a superconducting layer (e.g., of niobium) formed above the bridge layer and a normal conducting layer (e.g., of titanium) formed above the bridge layer. The bridge layer allows the device to be formed of superconducting and normal conducting material that are otherwise incompatible. A titanium normal conducting layer can be allowed to oxidize over a period of years.

Abstract: A quantum interference device includes a superconducting loop interrupted by a gap, a plurality of normal conductor segments bridging the gap; and an interferometer connected to the normal conductor segments, wherein the normal conductor segments are spaced apart. There may be 2N+1 normal conductor segments, where N is a positive integer, which may be of equal length and evenly spaced. The device produces a larger signal than a conventional quantum interference device.

Abstract: A quantum interference device comprises a superconducting loop interrupted by a gap; a plurality of normal conductor segments bridging the gap; and an interferometer connected to the normal conductor segments, wherein the normal conductor segments are spaced apart. There may be 2N+1 normal conductor segments, where N is a positive integer, which may be of equal length and evenly spaced. The device produces a larger signal than a conventional quantum interference device.

Abstract: A quantum interference device comprising a superconducting loop interrupted by a normal conductor segment, and an interferometer connected to the normal conductor segment wherein the superconducting loop comprises a plurality of turns. The turns can be a plurality of adjacent lobes. A coil can be located within a lobe of the superconducting loop. Optionally a bridge layer (e.g. of gold) is formed above the substrate to make an electrical contact between a superconducting layer (e.g. of niobium) formed above the bridge layer and a normal conducting layer (e.g. of titanium) formed above the bridge layer. The bridge layer allows the device to be formed of superconducting and normal conducting materials that are otherwise incompatible. A titanium normal conducting layer can be allowed to oxidise over a period of years.